Technical Field
The present invention relates to a ventilation structure of a light fixture for a vehicle.
Related Art
A light fixture for a vehicle is known that, within a lamp chamber that is partitioned-off and formed by a housing and a lens that covers the opening portion of the housing, houses a bulb that is a light source, a reflector that reflects light from the bulb, and an extension that covers the gap between the reflector and the housing. Further, suppression of fogging of the inner surface of the lens has conventionally been carried out by forming a breathing hole in the back surface of the housing at this light fixture for a vehicle, and communicating the lamp chamber and the exterior via this breathing hole, and ventilating the interior of the lamp chamber by convection of air due to the temperature difference within the lamp chamber.
Japanese Patent Application Laid-Open (JP-A) No. 2002-124123 discloses a technique of forcibly cooling a lighting control circuit by forcibly causing outside air to flow into a space that is surrounded by a reflector and a lamp housing at a front light for a vehicle and in which the lighting control circuit is housed. In this prior technique, outside air is forcibly made to flow by connecting a venturi, that generates negative pressure due to traveling wind flowing therealong, via a connection tube to the space in which the lighting control circuit is housed.
However, in the above-described prior technique, the connection tube opens at the peripheral wall of the venturi. Accordingly, the negative pressure is small when the traveling wind is slow, and therefore, it is thought that the traveling wind that flows along the venturi will penetrate into the connection tube, and further, will penetrate into the front light for a vehicle from the connection tube. Accordingly, there is room for improvement with regard to this point.